Most of us have become aware of the way that a relatively small piece of rock—an asteroid approximately the size of Manhattan Island or the Matterhorn—changed the course of life-history on this planet. It struck the Earth at 40,000 miles and hour, hitting what is now the northern coast of the Yucatan, generating a titanic explosion that ignited every plant standing above the ground, raising a tidal wave that swept over most of North America, and opening a chain of deadly volcanoes on the other side of the world, near India. The esteemed Bob Bakker to the contrary, the late, lamented dinosaurs, I believe, died from smoke inhalation.